The invention relates to a method of recording marks representing data, at a predetermined writing speed or at different writing speeds in an information layer of an optical information carrier by irradiating the information layer with a pulsed radiation beam. Each mark is written by a sequence of one or more pulses having a first radiation power level. The invention also relates to an optical recording device for carrying out the recording method. The method is suitable for direct-overwrite on an information carrier, i.e. by writing information to be recorded in the information layer of the carrier and at the same time erasing information previously written in the information layer. The method can be used for direct-overwriting in information layers made of a phase-change material.
The writing speed is the magnitude of the velocity between the information layer of the information carrier and a spot formed by the radiation beam on this layer. When writing data on an information carrier, the writing speed may change as a function of the position of the irradiating beam on the information layer. Changes in writing speed are encountered when writing on a disc-shaped information carrier rotating at a constant angular velocity. This applies both when writing at a radius-independent data rate and at a radially increasing data rate.
A recording method according to the preamble is known from the Japanese patent application no. JP-A 3-283021, the above citations are hereby incorporated herein in whole by reference.